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0 pointsComevius7y ago0 comments

Those warming periods are either local, are much, much slower and they are not supposed to be in sync with human activities either.

This one is much faster. Not everyone sees it of course. Change blindness is what they call it.

https://www.npr.org/sections/krulwich/2014/02/05/257046530/b...

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ilove_banh_mi7y ago· 1 in thread

This is not a correct description of past climate changes. The glacial and interglacial periods of the last 2.5 million years have been global and swinging temperatures by 6-9°C in either direction, with periods between 40-100k years.

During the last interglacial (Eemian, ca. 129–116k years ago) sea level was 6-9 meters higher than today; Scandinavia was an island. The water temperature of the North Sea was about 2°C higher than at present; hippos lived as far North as the Rhine and the Thames. The onset of the Eemian took just a few centuries, during which global temperatures shot up >5°C.

ComeviusOP7y ago

https://www.nature.com/articles/s41467-018-05314-1#ref-CR8

The Eemian was caused by reduced North Atlantic ocean circulation, a courtesy of the previous Saale glaciacion period, too much fresh water, and continued transfer of heat from the south.

It produced abrupt effects localized to high altitude areas. Most of what you described occured in the later stages of this 15000 year long period.

The Eemian cannot be really compared to the current global warming, a potential AMOC (Atlantic meridional overturning circulation) instability is just one out of the thousand problems we are facing.

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